Royal Bank of Canada says it has closed 40 client accounts following an internal review connected to last year’s Panama Papers release, a leak of documents from Panamanian law firm Mossack Fonseca which detailed the ownership structure of hundreds of thousands of secretive offshore shell companies.

J-F Courville, chief operating officer of RBC’s wealth management unit, said the accounts were closed because they no longer fell within the risk-tolerance levels based on industry standards. Courville said RBC will also introduce new measures “to strengthen account agreements with cross-border customers around tax requirements in their countries.”

“We are also going to continue enhancing the due diligence that we do on clients when operating in countries where automatic transfer of tax information doesn’t exist, including requesting confirmation that they’re filing their taxes on these accounts,” Courville said.